摘要 |
A failure of any one of three swashplate actuators of a helicopter rotor blade is detected. Once such a detection is made, the position of this nonfunctional swashplate is locked and measured. The inputted commanded swashplate collective position, commanded swashplate x-axis rotational position, and commanded swashplate y-axis rotational position are then passed to a failure-mode control matrix. The failure-mode control matrix computes swashplate actuator commanded positions for the two operable swashplate actuators so that aircraft attitude control is maintained. These two swashplate actuator commanded positions instruct positional movement of the rotor blade swashplate to thereby meet the commanded swashplate x-axis rotational position and the commanded swashplate y-axis rotational position which will control attitude. A quasi-swashplate-collective-position corrector computes the quasi-swashplate collective position that will occur because of the successful control of the aircraft's attitude. The swashplate-collective-position corrector then generates an amount of rotor blade lift attainable with a computed rotor blade speed change to compensate for any difference between the commanded swashplate collective position and the quasi-swashplate collective position. A closed loop vertical velocity controller refines the predicted rotor speed change that is commanded to correct for the loss of collective control. |